Three dimensional arrays of cobalt nanocrystals: Fabrication and magnetic properties

Cobalt nanocrystal three dimensional (3D) arrays were fabricated by deposition of a ferrofluid on a highly oriented pyrolitic graphite substrate and by applying a magnetic field parallel to the substrate during the deposition process. Depending on the strength of the magnetic field, regular stripes of cobalt nanocrystals are obtained. The influence of the deposition process parameters was investigated. The magnetic properties of these 3D arrays are discussed in terms of orientation of the easy axes and ferromagnetic domain formation. (C) 2002 American Institute of Physics.